grafana/public/app/plugins/datasource/mssql/partials/annotations.editor.html

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			<textarea rows="10" class="gf-form-input" ng-model="ctrl.annotation.rawQuery" spellcheck="false" placeholder="query expression" data-min-length=0 data-items=100 ng-model-onblur ng-change="ctrl.panelCtrl.refresh()"></textarea>
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        Show Help
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		<pre class="gf-form-pre alert alert-info"><h6>Annotation Query Format</h6>
An annotation is an event that is overlaid on top of graphs. The query can have up to three columns per row, the <b>time</b> column is mandatory. Annotation rendering is expensive so it is important to limit the number of rows returned.

- column with alias: <b>time</b> for the annotation event time. Use epoch time or any native date data type.
- column with alias: <b>text</b> for the annotation text.
- column with alias: <b>tags</b> for annotation tags. This is a comma separated string of tags e.g. 'tag1,tag2'.


Macros:
- $__time(column) -&gt; column AS time
- $__timeEpoch(column) -&gt; DATEDIFF(second, '1970-01-01', column) AS time
- $__timeFilter(column) -&gt; column BETWEEN '2017-04-21T05:01:17Z' AND '2017-04-21T05:01:17Z'
- $__unixEpochFilter(column) -&gt; column &gt;= 1492750877 AND column &lt;= 1492750877

Or build your own conditionals using these macros which just return the values:
- $__timeFrom() -&gt;  '2017-04-21T05:01:17Z'
- $__timeTo() -&gt;  '2017-04-21T05:01:17Z'
- $__unixEpochFrom() -&gt; 1492750877
- $__unixEpochTo() -&gt; 1492750877
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